Whether space-time exists should be neither controversial nor even conceptually challenging, given the definitions of "space-time," "events" and "instants." The idea that space-time exists is no more ...

We all need some space sometimes—but it's harder to find than you might think. How far into our universe do we have to go to ...

For a quarter of a century, humans have continuously occupied the International Space Station. Here's a look at how far we've ...